A process unit including a drum cartridge and developer cartridges is provided to an image forming apparatus such as a laser printer. In the drum cartridge, photosensitive drums are held. In the developer cartridges, toners are housed, and developing rollers to supply the toners to the photosensitive drums are held. In order for the developer cartridge to be replaceable with a new cartridge when toner in a developer cartridge runs out, the developer cartridge is removably mounted on the drum cartridge.
Among such types of image forming apparatuses, there is an image forming apparatus in which developing rollers are made capable of being pressed against and spaced from photosensitive drums (for example, see JP-A-2003-84647). In this image forming apparatus, during image formation, in order to satisfactorily transfer the toners to the photosensitive drums from the developing rollers, developer cartridges are pressed to make the developing rollers contact the photosensitive drums in a pressed state. On the other hand, during non-image formation, in order to prevent deformation and the like in the developing rollers by continuously pressing the same areas of the developing rollers by the photosensitive drums in non-rotating state, the developing rollers are spaced from the photosensitive drums.
Further, there is an image forming apparatus in which a memory is mounted on a cartridge removably mounted on the apparatus body, and information on history of image forming operations is recorded in the memory (for example, see JP-A-2001-215862).
However, in accordance with an image forming apparatus having a structure in which developing rollers are capable of being pressed against and spaced from photosensitive drums, the developer cartridge is moved in accordance with a pressing and spacing operation thereof. Therefore, when a memory is mounted on a developer cartridge, it is impossible to secure a connection between a terminal attached to the memory and terminals provided to the apparatus body, which makes it impossible to satisfactorily perform read/write of information to the memory.